It is known that currently containers for liquid, or granular or powdery products are diffused, such as, for drinks or detergents, made by means of semi-stiff or flexible sheet material, suitably folded up and sealed.
Such containers, both with parallelepipedal and bag shape, are folded and closed by means of a first longitudinal welding forming the tubular and a transversal welding in correspondence to the opposite top and bottom edges in such a way that the top is almost flat or has two pitches sloping outside the semi-stiff container.
These containers are often provided with the so called "open and close" devices, fastened to the edges of the pouring opening carried out on the top of each container.
Open and close devices are known mainly including a cap screwable to a hub previously welded onto the edge of the pouring opening, or a so-called "hinged" cap consisting of a base glued to the container onto the borders of the pouring opening and a tongue, hinged and removably couplable to the base, fit to make a tight closure of the container. The more recent embodiments of these last devices include the sealing of the pouring opening with a removable or tearable strip of suitable water-repellent material that is glued upon the edges of the opening in such a way to make a kind of "manufacturer warranty" and "tightness" for the product packaged inside the container before its initial fruition. This strip lies between the container and the tongue of the "open and close" device.
The fastening of such closing devices often has problems because particular apparatuses were carried out so as to be inserted into the pre-existing packaging lines of such containers without "open and close" devices in this way true and real "bottle necks" have been introduced in correspondence with such apparatuses for fastening the "open and close" devices to the containers.
The "open and close" devices fastened to the borders of a pouring opening often comprise also the fastening of the "guarantee seal" tongue so introducing a further snag in the packaging line.
A further disadvantage is that such "open and close" devices are made of thermoplastic material and have relatively high cost in comparison with the container and the packaged product.
Further disadvantage of such closures is that most closures are fixed to containers of liquid, granular or powdery products that normally must be quickly consumed because they are "fresh" products such as milk and fruit juices. In fact, once one of such containers is open for the first fruition it is necessary to consume briefly the remaining packaged product even if the container closure is hermetic. This latter, therefore, must not necessary be hermetic because the "aroma-saving cap" function is the only effectively required function. It is therefore evident that the actual hermetic closures are disadvantageously extremely expensive for the simple functions to be worked out: to save the aroma of the product still packaged inside the container and to insulate temporarily the product from the external environment.
The document GB-A-2233315 discloses a cartoon container spout incorporated into the container and including a membrane, impermeable by the container's contents.
This membrane initially prevents the contents from escaping but is relatively readily penetrated by the end-user without the end-user having to penetrate the carton wall. The membrane is incorporated into the spout region of the container in such a way that, when pulled or penetrated, it parts company with the surrounding spout material to leave a cleanly defined pouring opening in the spout.
A screw cap is provided for re-closing the threaded screw end region of the spout.
This cartoon spout is carried out integral with a closing membrane of its inner lumen, so preventing the filling of the container to which the spout is fixed.
The document EP-A-0435279 discloses a pouring plug for paper containers having flange portion corresponding to peripheral surface portion of fitting hole of container body and mounted from inside container body.
The plug has a threaded cap and a pourer, fitted through a thin wall section and having a lid and pull ring. The plug fitment is supported by a shoulder which contacts the inner edge of the fitting hole The space between the flange and the projection rim is greater than the thickness of the container so that a clearance remains after fitting.
During vibrations caused by container movement the projection shoulder and the flange butt to the edge of the fitting hole so that the fitment remains secure.
The main feature of this fitment is that it cannot be dislodged prior to supersonic fixing of the pouring spout to the container wall and there is no teaching about the method of sealing to a container a heat-deformable closure being sealable both before and/or after the container filling.
In the document EP-A-407746 it is disclosed a box-shaped packaging container with flat gable roof, made of folded plasticised blank and having a spout or adaptor for it in its flat gable roof. At the gable part, the flat roof is closed by a sealed seam and has a folded pocket consisting of triangular folding flaps at one corner.
In the opposite corner, between the flat roof and the adjacent body wall is an inclined surface which forms, together with side pocket surfaces on the adjacent sides a gable pocket inside the square outer shape.
This container is easy to handle, particularly due to the spout design and form, but having neither a very cheap heat-deformable closure, nor a closed end fixable closure.